Best sound i ever heard from closed-up portables. Every headphones i have tried after es10, sounds boring, without bass and muffled. I was never after big opened up headphones for home listening. No doubt ES10 cant compete with those. But in category of portable headphones, es10 is the king. And here is why:

Sound

bass - 53mm drivers can produce bass, which 42mm cant. It is not just about quantity, but also about how low it goes and how detailed and accurate it is.

soundstage - very close due to its slim profile

highs - no harshness or sibilance, lots of details there compared to for example es700 and probably most of portables

mids - great mids, good vocals (very much like es700, which i also own and probably close to sound of es7, which i didnt try though)

some said its V shaped, but in my opinion, people are just used on majority of portables, which are mid centric or lacking bass. Frequency response of es10 is quite balanced.

clarity - like i said, everything else i tried after es10 sounded muffed.

overall impression - balanced headphones with unique bass in its category, more fun than analytic, music is full of details and there is lot of liveliness and dynamic for portables

Build and looks

I used it a lot. Cups got scratches quickly. Other than that, its like new. Construction doesnt make sounds, it has still same clamping force. Even if scratched, its still best looking head gear i ever saw. Good think about es10 is also fact, that it doesnt make you look stupid thanks to its slim profile. Cabel is ideal for portable headphones. Short and thin.

Comfort

Thanks to its 53mm drivers, its more around ear than on ear...or something right in the middle. I find it very comfortable. One important thing here: If you want to get the best out of it, you should buy ear pads from ESW11 (limited edition of es10 with wooden cups instead of titanium and leather pads). Default ear pads on es10 are sadly from synthetic leather, which are less comfortable for long periods (it started to bother me usually after +- 1 hour) and makes your ears sweat. Leather pads also adds more premium feeling and some even say, that they like the sound more with leather pads, because they make more sound go in and out and add slightly distance between drivers and ears. Clapping force is exactly ideal. I can wear it for hours and also go running with it and it doesnt tend to move at all. Just perfect balance.

Portability

It weights more than most portable headphones like Momentum or es700 thanks to 53mm drivers, but its perfectly fine weight for portable use. Cups can rotate more than 90 degree so its also easy to put in bag or whatever you use for traveling. When it comes to isolation, it is somewhat mediocre. For me its perfect balance. I cant hear somebody talking in next room or hear my footsteps but can hear more louder sounds. I wouldnt feel comfortable completely without my hearing. You will hear cars, you will here street noise, metro noise. Its not ideal for commuting in noisy environment.

What is it for

These headphones are universal as in where to use, with what to use and what to play on them. Even if they have 53mm drivers, they dont need strong player or amp. It can take care of all music. Only negative in sound quality is lack of space. These headphones are so good sounding and comfortable (at least with leather pads), that i dont use them only for travel and sport, but also for gaming and home listening. There are of course better headphones to do the home listening job, but if you should have just one headphones and you dont mind paying premium price, you should have es10. The king of portable headphones.

I've own most Audio Technica Portables (es7, esw9, esw10jpn, m50) and some other phone (Denon a100, tried Ultrasone 780 & 580). And This is by far my best choice. This may not be as good as esw10 but it is much more comfortable. Unlike esw10 that has huge amount of clamping force, es10 pads sits lightly on your ears. Other than that the build quality in this non limited edition seems more sturdy than the esw10, I think the Denon A100 also have worse build quality compared to this, so I think this is my perfect portable phone: Sturdy, lightweight, comfortable, and beautiful (this may vary).

The sound is also not that bad; I think it sounds great; well it's sounds more consumer oriented compared to esw10. While ESW10 sounds much more natural and seems to be the "reference" quality for portable phone. This phone offers much more fun; it sounds more like m50 than to ESW10 mainly I think is due the bass quantity; Despite that I think it sounded better than m50, it has more bass extension and stronger mids. the bass might be boomy but it never dominates the rest of the spectrum like on other bassy phones. Despite that It also offer great extension and detail on bass. The midrange is what makes it an Audio Technica phones, warm and lush; though it might recess a bit on poorly recorded track. Soundstage is still small, a bit bigger than AT es line but smaller than A100. Separation is a bit poor compared to esw10, maybe due to bass. Headphone amplifier isn't a requirement but it does scale well; it gain more benefit compared to the old 42 mm AT driver. Nevertheless it's a great phone !

Some Updates, after few days using receiver as source I feel there are noticeable driven when driven by mp3 player that amp is just so so, I'm thinking of buying some Fiio or changing DAP

For a portable, the ES-10 has surprisingly substantial sub-bass--very similar to the M50, with both able to almost match the D7000 all the way down to 30Hz (although the D7000 does it effortlessly, while the two AT models struggle a little bit more). In fact. The ES-10 and the M50 sounded so similar to the point where I wondered if they use the same driver. It's a pleasant and warm sound without any sibilance, but not as articulate or airy as I'd like. Being a portable on-the-ear is fine since it's actually pretty comfortable, but I still prefer to not have something pressing on my ears at all. I wouldn't pick the ES-10 over the M50 since the M50 costs less than half but sounds so similar, and is more comfortable, being full-sized, not to mention it folds down and is quite portable.